Computer-assisted

Working down this list, we see more innovative approaches. The unmanned option using computer assisted operation (discussed in Section 11.2) would improve safety of personnel and reduce operating cost. This is an example of innovation and the use of technology by the engineer, and is driven by an awareness of safety. 

Monitoring and control of the production process will be performed by a combination of instrumentation and control equipment plus manual involvement. The level of sophistication of the systems can vary considerably. For example, monitoring well performance can be done in a simple fashion by sending a man to write down and report the tubing head pressures of producing wells on a daily basis, or at the other extreme by using computer assisted operations (CAO) which uses a remote computer-based system to control production on a well by well basis with no physical presence at the wellhead. 

Computer assisted operations (CAO) involves the use of computer technology to support operations, with functions ranging from collection of data using simple calculators and PCs to integrated computer networks for automatic operation of a field. In the extreme case CAO can be used for totally unmanned offshore production operations with remote... 

Artificial lift techniques are discussed in Section 9.6. During production, the operating conditions of any artificial lift technique will be optimised with the objective of maximising production. For example, the optimum gas-liquid ratio will be applied for gas lifting, possibly using computer assisted operations (CAO) as discussed in Section 11.2. Artificial lift may not be installed from the beginning of a development, but at the point where the natural drive energy of the reservoir has reduced. The implementation of artificial lift will be justified, like any other incremental project, on the basis of a positive net present value (see Section 13.4). 

Cohen, G. and F.A. DiBianca, The use of contrast-detail-dose evaluation of image quality in a computed tomographic scanner. Journal of Computer Assisted Tomography, 1979. 3(2) p. 189-195. 

Wehrli F W, MacFall J R, Shutts D, Breyer R and Flerfkens R J 1984 Mechanisms of contrast in NMR imaging J. Comput. Assist. Tomogr. 8 369-80... 

Bryant D J, Payne J A, Firmin D N and Longmore D B 1984 Measurement of flow with NMR imaging using a gradient pulse and phase differenoe teohnique J. Comput. Assist. Tomogr. 8 588-93... 

After approaches to the solution of the major tasks in chemoinformatics have thus been outlined, these methods are put to work in specific applications. Some of these apphcations, such as structure elucidation on the basis of spectral information, reaction prediction, computer-assisted synthesis design or drug design, are presented in Chapter 10. 

In 1967, work was presented from a Sheffield group on indexing chemical reactions for database budding. In 1969, a Harvard group presented its first steps in the development of a system for computer-assisted synthesis design. Soon afterwards, groups at Brandeis University and TU Munich, Germany, presented their work in this area. 

G. Folkers, Eds., Computer-Assisted Lead Finding and Optimization, Wiley-VCH, Weinheim, 1997, pp. 367-378. 

P7] N.A. B. Gray, Computer-Assisted Structure Elucidation, Wiley, New York, 1986. 

In the development of the CAMEO system (Computer-Assisted Mechanistic Evaluation of Organic reactions) [8 it was decided to treat large classes of mechanistically related reaction types by separate modules. 

Program systems for computer-assisted organic synthesis (CAOS) have been under development since the early 1970s [27]. The program systems for computer-assisted synthesis planning can be subdivided into two groups information-oriented and logic-oriented systems [28]. 

Zhang and co-workers worked on the structure-based, computer-assisted search for low molecular weight, non-peptidic protein tyrosine phosphate IB (PTPIB) inhibitors, also using the DOCK methodology [89], They identified several potent and selective PTPIB inhibitors by saeening the ACD. 

However, better use of spectral information for more rapid elucidation of the structure of a reaction product, or of a natural product that has just been isolated, requires the use of computer-assisted structure elucidation (CASE) systems. The CASE systems that exist now are far away from being routinely used by the bench chemist. More work has to go into their development. 

Computer-Assisted Organic Synthesis W. T. Wipke, W. J. Howe, Eds., ACS, Washington (1977). 

A computer assisted approach of heterocyclic structures (825, 826) predicted a new method of synthesis for the thiazole (826). This method was reported soon after by P. Dubs (807). The same program proposed two other methods not yet experimentally checked (827). 

Visual and computer-assisted identification of the structure of a sample analyzed by a mass spectrometer. 

Extmsion processing is highly automated. Some extmders may process over 9 t/h, and in one Ralston Purina plant (Davenport, Iowa) 30 extmders were operating in a single location. With computer assistance, one person can operate many different extmders, and several different foods can be produced simultaneously. These maybe different formulations or different colors and shapes to be packaged singly or combined into one variety pack. The differences in variety may be attributable only to added colors or different shapes. 

Fig. 2. Schematic of a multipurpose fine chemicals plant. Computer-assisted process control is utilized.

An alternative approach (78,79) is based on a set of possible reaction schemes that are used to generate potential new pathways. Under both approaches, the problem, in part, is how to evaluate the utiUty of a particular scheme. A computer-assisted approach to predicting potentially useful reactions has been developed (80). The union of existing capabiUties in modeling chemical stmctures with selecting reaction pathways has not yet taken place. 

The Frasca method for obtaining 1-arylindazoles also involves a C(3)—C(3a) ring closure (67CJC697). It consists in the cyclization of p-nitrophenylhydrazones of ketones and aldehydes with polyphosphoric acid. The Barone computer-assisted synthetic design program has found several new methods for preparing indazoles (79MI40409). The selected method involves the transformation of jV, jV -diphenylhydrazides (596) into 1-phenylindazoles (597) by means of trifluoromethanesulfonic anhydride. The yields vary from 2% (R = H) to 50% (R = Ph). 

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